P0351 Subaru Forester
Ignition Coil A Primary/Secondary Circuit Malfunction · Powertrain Code · High · Repair: Easy
What is P0351?
The ignition coil for cylinder 1 has an electrical fault.
When the Subaru Forester triggers code P0351 (ignition coil a primary/secondary circuit malfunction), it typically points to an issue in the powertrain system. This is a high severity code, so address it promptly to avoid further damage or safety concerns. Below you'll find the most common causes, symptoms, and repair options specific to the Subaru Forester.
This repair is rated easy, meaning basic tools, no lift needed.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Subaru Forester.
Common Causes on Subaru Forester
- Failed ignition coil on cylinder 1
- Coil connector corrosion from moisture under the hood
- ECM coil driver circuit failure
- Wiring harness damage to coil 1
Symptoms
- Check Engine Light on
- Cylinder 1 misfire
- Rough idle
- Loss of power
- Vibration
Notes for Subaru Forester
Subaru uses coil-on-plug; the flat boxer layout makes passenger-side coils (cylinders 1 and 2) very easy to access.